1. Field of Invention
Aspects of the present invention are directed to processing of a video signal, and more particularly to a system and method for minimizing distortion in a video signal.
2. Discussion of Related Art
Digital video signals contain compressed data in order to conserve system resources such as bandwidth and memory. To do so, the images that constitute the video signal can be divided into a series of quadrilateral segments, referred to as blocks, where each block contains at least one pixel, ordered by row and column. The data in each of these blocks can be transformed into a matrix of coefficients. These coefficients are then quantized into discrete values, and each quantized coefficient matrix is compressed to further reduce the matrix to a smaller array of discrete numbers. A Fourier related transform such as a discrete cosine transform (DCT) is an example of a transform that can be applied to each block to facilitate this data compression. Video compression standards associated with this type of compression include MPEG, JPEG, H.261, H.263, H.264, etc.
Some forms of compression can be lossy, and as such, a certain amount of data can be permanently lost during the compression process. Due to this data loss, a reconstructed image based on the compressed signal may not be identical to the image as it existed prior to its compression and encoding. Instead, the reconstructed image is an estimation of what the original image looked like. Various compression schemes seek to minimize the impact of the lost data by canceling redundant spatial or temporal data, nearly redundant data, or data that is deemed to be of less importance. Despite these efforts, compression of a video signal can still result in various unwanted compression artifacts and other humanly perceptible data errors.